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Archive for October, 2016

Mallet finger is an injury to the thin tendon that straightens the end joint of a finger or thumb. Although it is also known as “baseball finger,” this injury can happen to anyone when an unyielding object (like a ball) strikes the tip of a finger or thumb and forces it to bend further than it is intended to go. As a result, you are not able to straighten the tip of your finger or thumb on your own.

With a mallet finger injury, the fingertip droops and cannot be actively straightened.

Anatomy

Tendons are tissues that connect muscles to bone. The muscles that move the fingers and thumb are located in the forearm. Long tendons extend from these muscles through the wrist and attach to the small bones of the fingers and thumb.

The extensor tendons on the top of the hand straighten the fingers. The flexor tendons on the palm side of the hand bend the fingers.

The extensor tendons straighten the fingers and thumb through a very complex arrangement.

Description

In a mallet injury, when an object hits the tip of the finger or thumb, the force of the blow tears the extensor tendon. Occasionally, a minor force such as tucking in a bed sheet will cause a mallet finger.

The injury may rupture the tendon or pull the tendon away from the place where it attaches to the finger bone (distal phalanx). In some cases, a small piece of bone is pulled away along with the tendon. This is called an avulsion injury.

(Top) A rupture of the extensor tendon. (Bottom) A fragment of the distal phalanx has pulled away with the tendon.

The long, ring, and small fingers of the dominant hand are most likely to be injured.

Symptoms
The finger is usually painful, swollen, and bruised. The fingertip will droop noticeably and will straighten only if you push it up with your other hand.

Risk for Infection

It is very important to seek immediate attention if there is blood beneath the nail or if the nail is detached. This may be a sign of a cut in the nail bed, or that the finger bone is broken and the wound penetrates down to the bone (open fracture). These types of injuries put you at risk for infection.

A mallet finger injury requires medical treatment to ensure the finger regains as much function as possible. Most doctors recommend seeking treatment within a week of injury. However, there have been cases in which treatment was delayed for as long as a month after injury and full healing was still achieved.

Physical Examination

After discussing your medical history and symptoms, doctor will examine your finger or thumb. During the examination, doctor will hold the affected finger and ask you to straighten it on your own. This is called the mallet finger test.

During a mallet finger test, doctor determines whether you can straighten your fingertip without assistance.

X-rays

Doctorwill most likely order x-rays of the injury. If a fragment of the distal phalanx was pulled away when the tendon ruptured, or if there is a larger fracture of the bone, it will appear in an x-ray. An x-ray will also show whether the injury pulled the bones of the joint out of alignment.

This x-ray shows that a piece of the distal phalanx bone broke away with the tendon.

Treatment

Mallet finger injuries that are not treated typically result in stiffness and deformity of the injured fingertip. The majority of mallet finger injuries can be treated without surgery.
In children, mallet finger injuries may involve the cartilage that controls bone growth. The doctor must carefully evaluate and treat this injury in children, so that the finger does not become stunted or deformed.

Nonsurgical Treatment

Most mallet finger injuries are treated with splinting. A splint holds the fingertip straight (in extension) until it heals.

There are several types of splints used to treat mallet finger, many of them fabricated by hand therapists.

To restore function to the finger, the splint must be worn full time for 8 weeks. This means that it must be worn while bathing, then carefully changed after bathing. As the splint dries, you must keep your injured finger straight. If the fingertip droops at all, healing is disrupted and you will need to wear the splint for a longer period of time.

When removing the splint for cleaning and drying, the fingertip must stay in extension.

A temporary splint is applied with two pieces of tape.

Because wearing a splint for a long period of time can irritate the skin, your doctor may talk with you about how to carefully check your skin for problems. Your doctor may also schedule additional visits over the course of the 8 weeks to monitor your progress.

For 3 to 4 weeks after the initial splinting period, you will gradually wear the splint less frequently — perhaps only at night. Splinting treatment usually results in both acceptable function and appearance, however, many patients may not regain full fingertip extension.

For some patients, the splinting regimen is very difficult. In these cases, the doctor may decide to insert a temporary pin across the fingertip joint to hold it straight for 8 weeks.

Surgical Treatment

Doctor may consider surgical repair if there is a large fracture fragment or the joint is out of line (subluxed). In these cases, surgery is done to repair the fracture using pins to hold the pieces of bone together while the injury heals.

It is not common to treat a mallet finger surgically if bone fragments or fractures are not present. Surgical treatment of the damaged tendon usually requires a tendon graft — tendon tissue that is taken (harvested) from another part of your body — or even fusing the joint straight.

The posterior cruciate ligament is located in the back of the knee. It is one of several ligaments that connect the femur (thighbone) to the tibia (shinbone). The posterior cruciate ligament keeps the tibia from moving backwards too far.

An injury to the posterior cruciate ligament requires a powerful force. A common cause of injury is a bent knee hitting a dashboard in a car accident or a football player falling on a knee that is bent.

Anatomy

Two bones meet to form your knee joint: your thighbone (femur) and shinbone (tibia). Your kneecap sits in front of the joint to provide some protection.

Bones are connected to other bones by ligaments. There are four primary ligaments in your knee. They act like strong ropes to hold the bones together and keep your knee stable.

Normal knee anatomy, front view

Collateral ligaments. These are found on the sides of your knee. The medial collateral ligament is on the inside and the lateral collateral ligament is on the outside. They control the sideways motion of your knee and brace it against unusual movement.

Cruciate ligaments. These are found inside your knee joint. They cross each other to form an “X” with the anterior cruciate ligament in front and the posterior cruciate ligament in back. The cruciate ligaments control the back and forth motion of your knee.

The posterior cruciate ligament keeps the shinbone from moving backwards too far. It is stronger than the anterior cruciate ligament and is injured less often. The posterior cruciate ligament has two parts that blend into one structure that is about the size of a person’s little finger.

Description

Injuries to the posterior cruciate ligament are not as common as other knee ligament injuries. In fact, they are often subtle and more difficult to evaluate than other ligament injuries in the knee.

Many times a posterior cruciate ligament injury occurs along with injuries to other structures in the knee such as cartilage, other ligaments, and bone.

A complete tear of the posterior cruciate ligament, back view.

Injured ligaments are considered “sprains” and are graded on a severity scale.

Grade 1 Sprains. The ligament is mildly damaged in a Grade 1 Sprain. It has been slightly stretched, but is still able to help keep the knee joint stable.

Grade 2 Sprains. A Grade 2 Sprain stretches the ligament to the point where it becomes loose. This is often referred to as a partial tear of the ligament.

Grade 3 Sprains. This type of sprain is most commonly referred to as a complete tear of the ligament. The ligament has been split into two pieces, and the knee joint is unstable.
Posterior cruciate ligament tears tend to be partial tears with the potential to heal on their own. People who have injured just their posterior cruciate ligaments are usually able to return to sports without knee stability problems.

Cause

An injury to the posterior cruciate ligament can happen many ways. It typically requires a powerful force.

A direct blow to the front of the knee (such as a bent knee hitting a dashboard in a car crash, or a fall onto a bent knee in sports)

Pulling or stretching the ligament (such as in a twisting or hyperextension injury)

Simple misstep

Symptoms

The typical symptoms of a posterior cruciate ligament injury are:

Pain with swelling that occurs steadily and quickly after the injury

Swelling that makes the knee stiff and may cause a limp

Difficulty walking

The knee feels unstable, like it may “give out”

Doctor Examination

During your first visit, doctor will talk to you about your symptoms and medical history.

During the physical examination, your doctor will check all the structures of your injured knee, and compare them to your non-injured knee. Your injured knee may appear to sag backwards when bent. It might slide backwards too far, particularly when it is bent beyond a 90° angle. Other tests which may help your doctor confirm your diagnosis include X-rays and magnetic resonance imaging (MRI). It is possible, however, for these pictures to appear normal, especially if the injury occurred more than 3 months before the tests.

X-rays. Although they will not show any injury to your posterior cruciate ligament, X-rays can show whether the ligament tore off a piece of bone when it was injured. This is called an avulsion fracture.

Sagittal and coronal T2-weitghted magnetic resonance images of the knee, showing upward displacement of the PCL insertion at the tibia (a) and the displaced fragment of the lateral tibial condyle (b and c).

Treatment

Nonsurgical Treatment

If you have injured just your posterior cruciate ligament, your injury may heal quite well without surgery Your doctor may recommend simple, nonsurgical options.RICE. When you are first injured, the RICE method – rest, ice, gentle compression and elevation — can help speed your recovery.

Immobilization. Your doctor may recommend a brace to prevent your knee from moving. To further protect your knee, you may be given crutches to keep you from putting weight on your leg.

Physical therapy. As the swelling goes down, a careful rehabilitation program is started. Specific exercises will restore function to your knee and strengthen the leg muscles that support it. Strengthening the muscles in the front of your thigh (quadriceps) has been shown to be a key factor in a successful recovery.

Surgical Treatment

Your doctor may recommend surgery if you have combined injuries. For example, if you have dislocated your knee and torn multiple ligaments including the posterior cruciate ligament, surgery is almost always necessary.

Rebuilding the ligament. Because sewing the ligament ends back together does not usually heal, a torn posterior cruciate ligament must be rebuilt. Your doctor will replace your torn ligament with a tissue graft. This graft is taken from another part of your body, or from another human donor (cadaver). It can take several months for the graft to heal into your bone.

Procedure. Surgery to rebuild a posterior cruciate ligament is done with an arthroscope using small incisions. Arthroscopic surgery is less invasive. The benefits of less invasive techniques include less pain from surgery, less time spent in the hospital, and quicker recovery times.

Surgical procedures to repair posterior cruciate ligaments continue to improve. More advanced techniques help patients resume a wider range of activities after rehabilitation.

Rehabilitation

Whether your treatment involves surgery or not, rehabilitation plays a vital role in getting you back to your daily activities. A physical therapy program will help you regain knee strength and motion. If you had surgery, physical therapy will begin 1 to 4 weeks after your procedure.

How long it takes you to recover from a posterior cruciate ligament injury will depend on the severity of your injury. Combined injuries often have a slow recovery, but most patients do well over time.

If your injury requires surgery, it may be several weeks before you return to a desk job – perhaps months if your job requires a lot of activity. Full recovery typically requires 6 to 12 months.

Although it is a slow process, your commitment to therapy is the most important factor in returning to all the activities you enjoy.